The BBC committed a "major breach" of industry standards by failing to disclose that the voice of a film about the Gaza conflict was the child of a Hamas official, as ruled by UK media regulator Ofcom.
An probe by the media regulator into the documentary titled Gaza: How to Survive a Warzone has found that the film was "substantially inaccurate".
The BBC's director general had already issued an apology, saying there had been "a significant failing in relation to accuracy".
The authority has ordered the broadcaster to air a evening declaration about its decisions.
"Given this constitutes a significant violation of our code, we are directing the BBC to transmit a message of our findings against it on BBC Two at nine o'clock in the evening, with a schedule to be finalised," it said.
'Risk to Erode Credibility'
The watchdog's announcement said: "Our probe determined that the documentary's failure to disclose that the narrator's male guardian occupied a role in the Hamas-run authority was materially misleading.
"It meant that the public did not have critical information which may have been highly relevant to their assessment of the presenter and the content he shared.
"Confidence is at the heart of the connection between a media organization and its public, notably for a national broadcasting corporation such as the public broadcaster.
"This error had the potential to erode the very considerable degrees of trust that audiences would have put in a BBC factual programme about the conflict in Gaza."
The documentary was pulled from iPlayer in the month of February after the presenter's personal associations were revealed, and in this past July an corporation's own inquiry concluded it violated the corporation's content policies on accuracy.
A representative for the broadcaster commented: "The Ofcom ruling is in accordance with the results of Peter Johnston's review, that there was a significant failing in the film in relation to the BBC's Editorial Guidelines on truthfulness, which corresponds to Rule 2.2 of the regulator's media standards.
"We have apologised for this and we accept Ofcom's decision in complete. We will follow the sanction as soon as the date and language are finalised."
